Process of producing complemental parts



E. B. NICHOLS. PROCESS OF PRODUCING COMPLEMENTAL PARTS.

- APPLICATION FILED MAR-14.19.21. I I 1330,02 1, A e tedSept-26,1922.

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E. B. NICHOLS. PROCESS OF PRODUCING COMPLEMENTAL PARTS- APPLICATION FILED MAR. 14, 1921. 1,430,024.

Patented Sept. 26, 1922..

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piston rice.

EDGAR, B. NICHOLS, OF ROCHESTER, NEN YORK, ASSIGNOR TO AMERICAN FLYER MFG. (30., OF CHICAGO, ILLINOIS, A CORPORATION.

PROCESS OF PRODUCING COMPLEMENTAL EAR'IS.

Application filed March 14, 1921.

To all whom it may concern:

Be it known that I, EDGAR B. Nrorrons, a citizen ofthe United States of America, residing at Rochester, in the county of Monroe and State of New York, have invented certain new and useful Improvements in Processes of Producing Complement-a1 Parts, of which. the following is a full, clear and exact specification.

This invention relates to the manufacture of complemental metal plates, and has for its object to provide a process by which such plates can be produced from a single sheet of material without excessive cost, by which the desired fit between the several parts can be easily and accurately secured, and by which a. substantial saving of metal will be effected.

It is awell known fact that where a. blank is punched from sheet metal it can only be replaced in its original position by the application of considerable pressure, assuming that the blank can be properly located relative to the plate from which it was cut. li loreover it is difficult to mechanically change the dimensions of one of the parts a few thousands so that they will lit together either loosely or tightly as desired. At the present time sheet metal parts which are complemental in the sense that they are combined together to form the cooperating parts of one unit, such as the halves of a hinge joined by a pintle, or a punch and die, are made separately, necessitating the use of tools for each part. If a single tool is used to cut the parts from a sheet of metal they must be carefully fitted by hand, as byfiling or mechanically obtaining the desired clearance between the parts. This is expensive and unless very carefully done, inaccurate. l have successfully produced parts which cooperate from a single sheet of metal with the use of a single punch and die, by cl taining the desired working clearance be tween the several parts by etcl'iing. This is a cheap and accurate method which requires but little time and no skilled labor. lVhilc my invention is applicable to a large number of uses I will describe by way of illustration, its use. in making a light punch and die such as is shown in my application for patent, Serial No. 345,429, filed December 16th, 1919. My present invention is particularly useful in making such punches in quantity. As illustrating the general. ap-.

Serial No. 452,375.

plication of my invention to the making of complemental metal parts I have also shown a hinge as asecond embodiment, and a floor plate as a third.

Coming now to the drawings, in which like reference characters denote like parts throughout: Y F ig. 1 is a plan of a metal blank for makmg a punch in accordance with, and illustrating the first embodiment of my invention;

Fig. 2 shows the same blank with one complementa-l part punched therefrom;

Fig. 3 is a perspective of the blank bent to form a punch, showing the assembling of the complemental parts; I

Fig. ej is a perspective of the completed punch and die;

Fig. 5 is a perspective showing a number of parts held by a. rod for etching;

F ig. 6 is a fragmentary elevation of parts ready for etching; s

Fig. 7 is a section-through a tank of etching solution, with parts suspended therein;

Fig. 8 is a plan of a. metal blank from which the complemental parts of a hinge are made in accordance with, and illustrating a second embodiment of my invention;

Fig. 9 is a plan of the complemental parts out from the sheet metal;

Fig. 10 isan end elevation of the parts of the hinge and the hinge pintle;

Fig. 11 is a perspective of the completed hinge;

Fig. 12 is a plan of a floor plate blank;

Fig. 13 is a plan of the completed floor plate lock; and

Fig. 14 is a side elevation of a number of parts held by a clamp for etching.

As shown in Figs. 1 to 6 inclusive, I illustrate a light paper punch-made in accordance with my invention. The complemental parts here are the punch, or male die, and the die, or female die. This punch is made from sheetor strip metal, and as shown in Fig. 1 blanks 1 are first cut out. With a punch shaped as shown in dashed lines at 2 in this figure the star 3 is punched from the blank 1 leaving the female die 4. The blank is then folded upon the dashed line Fig. 2 and the ends 5 and 6 are temporarily held by a clamp C. Thepunchings or stars 3 are perforated at 7, preferably before beingcut from the metal, this aperture being convenient for stringing them 111301 8% hail g r H, by which they are suspended in a tank T filled with an etching; bath E. In Fig. 5 a series of parts 3 are shown upon a hanger. If desired these parts can be left unperi orated and held by a clamp 40 as shown in Fig. M. In F 1g. 6, I show the stars 3 as having their sides covered with an acid resisting coating 8, such as wax. In practice, however. I donot find this coating essential. After etching the male die 3 until its pe riphery is sulliciently reduced, the star is placed in the female die I; andywith the ends Sand 6 clamped as in Fig. 3 the male part 3 is fastened to the endG in any suitable manner. Although the parts may be sweated together, I prefer to spot weld them. this being indicated by shading at 8. The dimension of the slot between the male and female dies is exaggerated in scale for the sake of clearness. Fig. I shows the completed punch with the complemental parts 3 and 4 made from a single piece of metal, and also by the use of a single punching.

In the above described embodiment of my invention I have found that where the blank is made of cold rolled steel of approximately .040 thick, that a clearance of .005 between two edges of the Cooperating complemental parts 3 and t produces the desired working fit for paper cutting. To etch off this amount I first clean the parts with gasoline or benzi'ne and then immerse them in a bath consisting of et parts of nitric acid to one part water. By trial a table can be readily computed which will indicate the reduction per minute. I have found that the time may Vary considerably with changing conditions.

I have shown a hinge as illustrating; a second article having: cooperating complemental parts, illustrating this embodiment in Figs. 8 to ll, inclusive. Here a metal plate or strip 13 is cut into parts by a single punching. The die should be shaped as shown in the shaded portion at 16. roue'hly E shaped. so that by cutting every other space or by stamping out the E shaped portions shown in dashed lines, a series of coinplemental parts. 14.- and 15. will be formed. Screw perforations 1.8 are preferably first punched in the metal. although this operation can be done simultaneously with the blanking; The parts 14- and 15 can be joined by a pintle 91 after one section is etched and the piutle seats are rolled up as shown at 2 and 23. Fig 10. I, therefore, suspend one section of the hinge in an etching bath reducing the edges 24 of the pintle seats 23 until the parts cooperate with the desired freedom of movement.

As a third embodiment I show a floor plate 30 and connection 31 such as are commonly used 1n gymnasium floors for support ing apparatus stays. The plate 30 is formed from sheet metal, and a punch cuts out a complemental part 31. This part (or the plate 30) is suitably etched in acid until. the dimensions oil the complemcntal parts are such that part 31 forming a locking bar, can readily be thrust through the aperture 32. A stay wire 33 is anchored to part so that by enterin and turning part 31 in plate 30 the stay can be securely held under tension. The plate 80 is preferably sunk in the floor 35, so to be flush'therewith. the floor having a cut away portion 30 in which the locking bar 3]. can turn.

Having thus described my invention what I claim as new and desire to secure by Let ters Patent is:

1. The process of prodiicinc coo iierating complement-a1 parts from a single piece ot sheet metal which consists in Si':!]]'l[')llll one part From the other, etching a cooperating edge of at least one of the parts thereby producing the desired clearance between the several parts.

2. The process of: making cooperating complemental parts from a single piece of sheet metal which comprises stamping one part from the other. and securing the desired fit between the edges of the cooperating parts thus formed by etching.

3. The process of producing complemental parts of sheet steel which consists in striking one part from the other, changing a dimen sion of at least one of the cooperating edges oi the complemental parts by suspending it in a solution of nitric acid and water until the desired tit is secured.

a. The process of making coinplemental metal parts for a punch and die which comprises stamping the male punch from:v the female die. etching the edges of one of the parts until the two parts will cooperate with the desired lit.

5. The process of making complcmental. metal parts for a punch and die which consists in stampingthe punch from the die, and causing t m parts to cooperate by changing the dimensions of one of them to a predetermined dcgrce by etching.

(i. The process of (()]1St1'll0l3lill complemental metal parts for a punch and die from sheet metal which comprises the following: steps: first. punching; the male punch from the sheet metal. thus leaving the female die; and second. etching the periphery of the male die, reducing the dimensions thercol to a predetermined degree: whereby a smooth working fit will be secured between. the several parts.

Signed at Rochester, N. Y., this 5th day of March 1921.

EDGAR B. NICHOLS. 

